Alkermes plc, a pharmaceutical company, has announced that alixorexton, a new investigational oral drug, has been granted orphan drug designations by regulatory bodies in both the United States and Europe. Specifically, the European Commission has given this designation to alixorexton for the treatment of narcolepsy, a rare, chronic neurological disorder.
Orphan drug designation is a status granted to medicines that are being developed to treat rare diseases. This designation aims to incentivise pharmaceutical companies to invest in research and development for conditions that affect a small number of people, making them less commercially attractive. In the European Union, this can include benefits such as protocol assistance, reduced regulatory fees, and potentially up to 10 years of market exclusivity if the drug is approved. These incentives are crucial for bringing new treatments to patients with rare conditions, where unmet medical needs are often high.
Alixorexton is a selective orexin 2 receptor (OX2R) agonist, meaning it works by targeting specific pathways in the brain related to wakefulness. Narcolepsy, which affects the brain's ability to regulate the sleep/wake cycle, often leads to excessive daytime sleepiness, sleep paralysis, and disturbed nighttime sleep. Narcolepsy type 1, in particular, is characterised by the loss of orexin-producing neurons and is associated with cataplexy – a sudden loss of muscle control triggered by strong emotions. Idiopathic hypersomnia (IH), another condition for which alixorexton is being developed, is also a rare neurological sleep disorder marked by excessive daytime sleepiness despite normal sleep durations, often accompanied by severe sleep inertia and cognitive dysfunction.
The drug is currently in advanced stages of clinical development. It is being evaluated in Phase 3 clinical trials, known as the Brilliance Studies, for adults with narcolepsy type 1 and type 2. Additionally, a Phase 2 study, Vibrance-3, is ongoing for adults with idiopathic hypersomnia. These trials are critical steps in determining the drug's safety and efficacy before it can be considered for regulatory approval and made available to patients.
According to Dr. Craig Hopkinson, Chief Medical Officer at Alkermes, these orphan drug designations are significant milestones for the alixorexton programme. He highlighted the substantial unmet need that still exists for patients with narcolepsy and idiopathic hypersomnia, underscoring the potential of alixorexton to advance care for these communities if it receives approval. The company anticipates completing the Vibrance-3 Phase 2 study for IH this year, alongside ongoing enrolment in the Phase 3 Brilliance Studies.
The development of new treatments like alixorexton is vital for patients in the UK living with these debilitating conditions. Current treatments for narcolepsy and idiopathic hypersomnia often focus on managing symptoms rather than addressing the underlying causes. For instance, NHS guidelines for narcolepsy often recommend lifestyle adjustments, scheduled naps, and stimulant medications to manage excessive daytime sleepiness. A drug that targets the orexin pathway could offer a more targeted approach, potentially improving quality of life for those affected. While precise UK prevalence figures for idiopathic hypersomnia are not readily available, narcolepsy is estimated to affect around 1 in 2,500 people in the UK, according to the NHS.
Source: Alkermes plc